[Android] Fixed SelectionLength Not Updated Correctly for Right-to-Left Text Selection on Editor and Entry

src/Controls/tests/DeviceTests/Elements/Editor/EditorTests.Android.cs

@@ -3,6 +3,7 @@
 using AndroidX.AppCompat.Widget;
 using Microsoft.Maui.Controls;
 using Microsoft.Maui.Handlers;
+using Microsoft.Maui.Platform;
 using Xunit;
 
 namespace Microsoft.Maui.DeviceTests
@@ -34,11 +35,7 @@ static int GetPlatformCursorPosition(EditorHandler editorHandler)
 		static int GetPlatformSelectionLength(EditorHandler editorHandler)
 		{
 			var textView = GetPlatformControl(editorHandler);
-
-			if (textView != null)
-				return textView.SelectionEnd - textView.SelectionStart;
-
-			return -1;
+			return textView?.GetSelectedTextLength() ?? -1;
 		}
 
 		Task<float> GetPlatformOpacity(EditorHandler editorHandler)
@@ -139,6 +136,33 @@ public async Task RotationYConsistent()
 			Assert.Equal(expected, platformRotationY);
 		}
 
+		[Fact]
+		[Description("The SelectionLength property should handle right-to-left text selection correctly and not return negative values")]
+		public async Task SelectionLengthRightToLeft()
+		{
+			var editor = new Editor()
+			{
+				Text = "Hello World"
+			};
+
+			var handler = await CreateHandlerAsync<EditorHandler>(editor);
+			var platformControl = GetPlatformControl(handler);
+
+			await InvokeOnMainThreadAsync(() =>
+			{
+				platformControl.SetSelection(5, 0);  // SelectionStart=5, SelectionEnd=0
+				int platformSelectionLength = GetPlatformSelectionLength(handler);
+				Assert.True(platformSelectionLength >= 0,
+					$"Platform selection length should never be negative, but got: {platformSelectionLength}");
+				Assert.Equal(5, platformSelectionLength);
+
+				// The virtual view should also show positive selection length
+				Assert.True(editor.SelectionLength >= 0,
+					$"Virtual view selection length should never be negative, but got: {editor.SelectionLength}");
+				Assert.Equal(5, editor.SelectionLength);
+			});
+		}
+
 		[Fact]
 		[Description("The Rotation property of a Editor should match with native Rotation")]
 		public async Task RotationConsistent()

src/Controls/tests/DeviceTests/Elements/Entry/EntryTests.Android.cs

@@ -3,6 +3,7 @@
 using AndroidX.AppCompat.Widget;
 using Microsoft.Maui.Controls;
 using Microsoft.Maui.Handlers;
+using Microsoft.Maui.Platform;
 using Xunit;
 
 namespace Microsoft.Maui.DeviceTests
@@ -33,13 +34,8 @@ static int GetPlatformCursorPosition(EntryHandler entryHandler)
 		static int GetPlatformSelectionLength(EntryHandler entryHandler)
 		{
 			var editText = GetPlatformControl(entryHandler);
-
-			if (editText != null)
-				return editText.SelectionEnd - editText.SelectionStart;
-
-			return -1;
+			return editText?.GetSelectedTextLength() ?? -1;
 		}
-
 		Task<float> GetPlatformOpacity(EntryHandler entryHandler)
 		{
 			return InvokeOnMainThreadAsync(() =>
@@ -165,6 +161,33 @@ public async Task RotationConsistent()
 			Assert.Equal(expected, platformRotation);
 		}
 
+		[Fact]
+		[Description("The SelectionLength property should handle right-to-left text selection correctly and not return negative values")]
+		public async Task SelectionLengthRightToLeft()
+		{
+			var entry = new Entry()
+			{
+				Text = "Hello World"
+			};
+
+			var handler = await CreateHandlerAsync<EntryHandler>(entry);
+			var platformControl = GetPlatformControl(handler);
+
+			await InvokeOnMainThreadAsync(() =>
+			{
+				platformControl.SetSelection(5, 0);
+				int platformSelectionLength = GetPlatformSelectionLength(handler);
+				Assert.True(platformSelectionLength >= 0,
+					$"Platform selection length should never be negative, but got: {platformSelectionLength}");
+				Assert.Equal(5, platformSelectionLength);
+
+				// The virtual view should also show positive selection length
+				Assert.True(entry.SelectionLength >= 0,
+					$"Virtual view selection length should never be negative, but got: {entry.SelectionLength}");
+				Assert.Equal(5, entry.SelectionLength);
+			});
+		}
+
 		//src/Compatibility/Core/tests/Android/TranslationTests.cs
 		[Fact]
 		[Description("The Translation property of a Entry should match with native Translation")]

src/Core/src/Platform/Android/EditTextExtensions.cs

@@ -261,10 +261,18 @@ static int GetSelectionStart(EditText editText, ITextInput entry)
 
 		static int GetSelectionEnd(EditText editText, ITextInput entry, int start)
 		{
-			int end = start;
 			int selectionLength = entry.SelectionLength;
-			end = System.Math.Max(start, System.Math.Min(editText.Length(), start + selectionLength));
-			int newSelectionLength = System.Math.Max(0, end - start);
+			int end = Math.Max(start, Math.Min(editText.Length(), start + selectionLength));
+			int newSelectionLength = Math.Max(0, end - start);
+
+			// If 'start > editText.SelectionEnd', it indicates a reverse selection (right-to-left selection),
+			// where the user selected text starting from the right and moving to the left.
+			if (start > editText.SelectionEnd && selectionLength > 0)
+			{
+				end = editText.SelectionEnd;
+				newSelectionLength = selectionLength;
+			}
+
 			// Updating this property results in UpdateSelectionLength being called again messing things up
 			if (newSelectionLength != selectionLength)
 				entry.SelectionLength = newSelectionLength;
@@ -274,8 +282,7 @@ static int GetSelectionEnd(EditText editText, ITextInput entry, int start)
 		// TODO: NET8 issoto - Revisit this, marking this method as `internal` to avoid breaking public API changes
 		internal static int GetSelectedTextLength(this EditText editText)
 		{
-			var selectedLength = editText.SelectionEnd - editText.SelectionStart;
-			return Math.Max(0, selectedLength);
+			return Math.Abs(editText.SelectionEnd - editText.SelectionStart);
 		}
 
 		internal static void SetInputType(this EditText editText, ITextInput textInput)